ABSTRACT The University of Illinois at Chicago (UIC) has a substantial NIH-funded basic science and translational research mission focused on inflammatory as well as obstructive and restrictive pulmonary pathologies. This involves program (P01), project (R01), and training grants (T32) from NHLBI, NCI, NIBIB, and NIEHS related to diagnosis, treatment and mechanisms of lung cancer, radiation-induced lung injury, acute respiratory distress syndrome, sickle cell-linked acute chest syndrome, acute lung injury and transplant obliterative bronchiolitis. In this context, scientists are conducting animal and human subject studies leading to improved understanding of the mechanisms and methods for regulation of lung vascular and alveolar permeability and wound healing and repair as well as the lung?s interaction with innate immunity, and how these are affected by regional ventilatory changes and challenges. While much of this research benefits from advances in imaging at microscopic and macroscopic scales, in vivo and in vitro, current in vivo imaging tools are a limiting factor, particularly in terms of their inability to provide quantitative functional imaging of ventilation and gas exchange at the endothelial barrier with meaningful resolution. UIC also has significant expertise and shared instrumentation facilities for developing and conducting research utilizing magnetic resonance imaging (MRI) including a 30 cm bore 9.4 Tesla MRI for small animal studies and clinical (1.5 and 3 Tesla) MRI systems for large animal and human subject studies. Most MRI measurements are conducted based on proton (hydrogen atom 1H) imaging. Unfortunately, the lungs are the one soft tissue region in the body where 1H imaging suffers from such bad noise due to lack of signal that it is not considered of value in all but a few types of lung imaging protocols. Over the past few decades hyperpolarized noble gas MR imaging, specifically 3He(lium) and 129Xe(non), has been shown to provide an attractive alternative for imaging of the structure of the airways. 129Xe has the added benefit that it dissolves within the blood stream and biological tissue with distinct chemical shift values relative to the gas phase and each other that are approximately 40 times higher than in proton based MRI. Therefore, the state of 129Xe, dissolved (in tissue or blood) or free, can be quantitatively differentiated with high resolution. This is invaluable in quantifying regional gas exchange, vascular permeability and transmembrane diffusion. Recent technological advances have resulted in the availability of easily operated commercial systems for providing hyperpolarized 129Xe. We propose to acquire such a system, which will be used first and foremost to expedite and improve the outcomes of our ongoing NIH-funded animal- based pulmonary research described herein. Additionally, this device will be a resource available to other NIH- funded researchers at UIC, as well as at neighboring Rush University Medical Center, Jesse Brown VA, Northwestern University, Loyola University Medical School, and University of Chicago. Existing agreements between these institutions and UIC facilitate shared usage of core instrumentation.